Coordinates selection switch assembly with slider bar actuator with permanent magnets activating reciprocating mercury wetted conductive plunger engaging multi-planar fixed contact array

ABSTRACT

Coordinates selection switch which comprises two groups of rectangular metal crossbars, each group being formed of parallel bars and the groups lying in interlaced equidistant levels. The crossbars are contained in a moulded plastics block and hermetically sealed cylindrical channels extend through the block and the cross-bars at the intersections thereof. Pistons made of magnetic material and having metal rings are disposed in the channels. Two groups of displaceable and rectangular operating bars are disposed on each side of the block and magnets are inserted into these operating bars at the same spacing from one another as the channels. The outside surface of the piston rings and the crossbar edges which appear in the channels are wetted by mercury for providing good contacts.

United States Patent [1 1 Lucas et al.

Inventors: Pierre M. Lucas,

lssy-les-Moulineaux; Auguste A. Sautel, Bonneuil-sur-Marne; JacquesChauvin, Verrieres-le-Buisson; Daniel J. Srzac, Bretignysur-Orge; JackB. Cibert, Creteil, all of France Filed: Sept. 20, 1971 Appl. No.:181,945

Foreign Application Priority Data Sept. 23, 1970 France 7034389 US. Cl.200/1 R, 200/16 D, 200/177,

200/234, 335/206 Int. Cl. H0lh 63/34, H0lh 36/00 Field of Search 200/1R, 16 C, 16 D,

[ 1 Oct. 23, 1973 Primary Examiner-J. R. Scott AttorneyAbraham A.Saffitz [57] ABSTRACT Coordinates selection switch which comprises twogroups of rectangular metal crossbars, each group being formed ofparallel bars and the groups lying in interlaced equidistant levels. Thecrossbars are contained in a moulded plastics block and hermeticallysealed cylindrical channels extend through the block and the cross-barsat the intersections thereof. Pistons made of magnetic material andhaving metal rings are disposed in the channels. Two groups ofdisplaceable and rectangular operating bars are disposed on each side ofthe block and magnets are inserted into these operating bars at the samespacing from one another as the channels. The outside surface of thepiston rings and the crossbar edges which appear in the channels arewetted by mercury for providing good contacts.

3 Claims, 14 Drawing Figures PAIENIEDHBI23 ma SHEET 1 BF 3 INVENTORS:

P. M. LUCAS, A. A. SAUTEL, J. CHAUVIN,

and D. J. SEREZAC, J. B. CIBERT By M ATTORNEY PATENTED UN 2 3 I975 SHEET2 [IF 3 IIII LO INVENTORS:

P. M. LUCAS, A. A. SAUTEL, J. CHALVIN,

D. J. SEREZAC and J. 25. 011mm A'FlUkNEY COORDINATES SELECTION SWITCHASSEMBLY WITH SLIDER BAR ACTUATOR WITII PERMANENT MAGNETS ACTIVATINGRECIPROCATING MERCURY WETTED CONDUCTIVE PLUNGER ENGAGING MULTI-PLANARFIXED CONTACT ARRAY The invention relates to a magnetically controlledcoordinates selection or crossbar switch using mercury at itscrosspoints.

U.S. Pat. No. 3,592,990 issued July I3, 1971 relates to a switch of thekind specified having crosspoints in the form of mercury drops trappedin cavities in moving pistons movable mechanically between aninoperative position, in which the mercury drops make contact with oneof the bars extending across a matrix, and an operative position, inwhich the drops make contact with two bars extending at right-angles toone another across the matrix. Such switches operate satisfactorily, butmeasures must be taken to prevent oxidation and mercury leaks. Thepistons and cylinders must therefore be precision-engineered, so thatthe production cost of the switch is high.

In this invention, in association with a matrix comprising bars atright-angles to one another, the cylinders and pistons form a unithermetically sealed in an inert atmosphere. Consequently, the pistonscannot be mechanically operated and operation is magnetic, the pistonsbeing made of a magnetic material. Instead of mercury drops being usedto make contact between two metal bars, contact is made between metalparts of mercury-wetted pistons and matrix bar parts whose edge appearsin the channels where the pistons move and which too are mercury-wetted.The mercury, although not forming drops, is essential for switchoperation, since experience shows that, in cases in which a pistonhaving metal zones separated from one another by insulating gaps movesin a channel which serves as a cylinder for the piston and which alsohas metal zones separated from one another by insulating gaps, contactbetween the metal zones of the piston and the metal zones of thecylinder is unsatisfactory unless the metal parts which form the zonesare mercury-wetted.

The invention will now be described in detail with reference to theaccompanying drawings wherein FIG. 1 is an exploded view of the switchaccording to the invention FIGS. 2 and 3 are sectional views of theswitch ona plane extending through the axis of a piston-receivingchannel, the piston being shown in its inoperative position in FIG. 2and in its operative position in FIG. 3

FIG. 4 is a detailed view of the switch electromagnets; and

FIGS. 5a to Sc and 6a to 6g show the operation of the crossbar switchaccording to the invention.

Referring to FIG. 1, two rectangular groups or families of metal strips2, 3 are received in an insulating plastics block 1. In FIG. 1 thestrips are shown as being horizontal and the block 1 and the strips 2, 3are pierced with a number of apertures 4 which are aligned along avertical axis 5 and which co-operate to serve as channels to guide thepistons. The channels or orifices 4 form a squared or checkerworkpattern. Pistons 6 can be displaced in the channels 4. A piston 6comprises a magnetic cylindrical rod 7 having an insulating covering 8to which rings 9 of the same material as the trips 2, 3 are securedconcentrically. The rings 9 are therefore insulated electrically fromthe rod 7; the piston is a plastics-covered element.

Two insulating plates 10, 11 are secured, e.g. by sticking, to thematrix top and bottom surfaces. Each plate 10, 11 is formed withfamilies or groups of parallel grooves l2, 13 on its outside surface;the grooves 12, 13 are on the same alignments as the bars and thegrooves of one group or family extend at right-angles to the grooves ofthe other group or family. The plates 10, ll serve to close the matrixhermetically and are positioned after the pistons 6 have been introducedinto the channels 4 and in an inert atmosphere.

Actuating bars or rods 14, 15 slide in the grooves l2, 13; they are madeof an insulating material and comprise inserted magnets 16 which areprovided to the same number and at the same pitch as the pistons in thematrix. All the magnets 16 are magnetized the same way round as oneanother, the direction of the magnetic field being parallel to thepiston axis.

Springs 17 in the form of bent strips are received in rectangularapertures 18 in the block I, one end 19 of the strip 17 extending beyondthe aperture 18. End 19 extends through an aperture 20 at the end ofeach actuating bar l4, 15. The rods 14, 15 are operated by solenoids 21,22 whose moving cores 23 are connected to the bars l4, 15.

Referring now to FIGS. 2 and 3, the outside surface of the rings 9 andthe edges of the apertures in the bars 2, 3 are covered by a mercuryfilm 24 which is essential for proper operation of the switch.

Referring to FIG. 4, the solenoids 21 (and 22) are retained between twomembers 25, 26 formed with complementary substantially hemicylindricalrecesses 27, 28, the members 25, 26 being secured by screws 29 toclosure plate 10. Screws 31, 32 secure a side member 30 to the members25, 26.

Operation of the switch according to the invention will be describedwith reference to FIGS. 5a to Sc and 6a to 6g.

Referring to FIG. 5a, magnet 16 of bar 14 does not attract piston 6,which is retained in its inoperative position by magnet 16 of bar 15. InFIG. 5b magnet 16 attracts piston 6. In FIG. Sc magnet 16 does notattract piston 6, which stays retained by magnet 16. Each of the rodshas three positions central (c) in which the magnet is centered on thepiston axis, remote (r) in which the magnet is relatively distant fromthe piston, and intermediate (i) in which one magnet side is tangent tothe piston axis. It results that a piston is attracted when theassociated upper magnet is in a central position, the associated lowermagnet being in a remote position.

FIGS. 6a to 63 represent the consecutive phases of connecting, holdingand disconnecting a piston. To keep the explanation clear, it will beassumed that the two bars 14, 15 associated with the piston are disposedin the same vertical plane as one another, although they are in factperpendicular.

In FIG. 6a'(16 r; 16' i) the piston is in its inoperative position andthere is no connection. In FIG. 6b (16 r; 16' r) rod 15 has been pulledto the left and the piston remains in its inoperative position (as doall the pistons associated with bar 15). In FIG. 6c (16 i 16' r) rod 14has been pulled to the left and magnet 16, as it moves into the positionof FIG. 5b I6 c; 16 =r), attracts piston 6. A connection is made but theother pistons controlled by bar 14 are not attracted. In

FIG. 6d (16 =i; l6 =i) the bar 15 is released and the piston remains inits operative position (same case as FIG. 5c). In FIG. 6e (16 r; 16 =i)the bar 14 is released and the piston remains in its operative position(same case as FIG. 5a). In FIG. 6f( 16 r; 16' r) the rod .15 is pulledto the left and the piston returns to its inoperative position to breakthe connection. In FIG. 6g 16 r; 16' =1), the rod is released and thepiston remains in its inoperative position.

What we claim is .1. A coordinates selection switch comprising twogroups of crossed conductive metal bars, one said group comprisingparallel bars which extend in a given I direction and which are disposedin planes at given evenly distributed levels, the other group comprisingparallel bars which extend at right-angles to said given direction andwhich are disposed at evenly distributed levels between said givenlevels, a moulded insulating plastics block receiving said crossed bars,cylindrical channels in checkerwork pattern extending through saidblockand said crossed bars at the intersections thereof, pistons made ofmagnetic material, having metal rings and disposed in said channels,means for hermetically closing said channels, two groups of displaceableoperating bars, the first group being in the form of bars providingoperation in a given direction which are disposed on one side of saidblock and the second group in the form of bars providing operation in adirection perpendicular to said given direction which are disposed onthe other side of said block, magnets inserted into said operating barsat the same spacing from one another as the channels, the outsidesurface of said piston rings and said crossed-bar edges which appear insaid channels being wetted by mercury.

2. A coordinates selection switch comprising two groups of crossedconductive metal bars, one said group comprising parallel bars whichextend in a given direction and which are disposed in planes at givenevenly distributed levels, the other group comprising parallel barswhich extend at right-angles to said given direction and which aredisposed at evenly distributed levels between said given levels, amoulded insulating plastics block receiving said crossed bars,cylindrical channels in checkerwork pattern extending through said blockand said crossed bars at the intersections thereof, pistons including amagnetic core, an insulating sheath and, disposed thereon, metal ringsat discrete zones, said pistons being disposed in said channels, meansfor hermetically closing said channels, two groups of displaceableoperating bars, the first group being in the form of bars providingoperation in a given direction which are disposed on one side of saidblock and the second group in the form of bars providing operation in adirection perpendicular to said given direction which are disposed onthe other side of said block, magnets inserted into said operating barsat the same spacing from one another as said channels, the outsidesurface of'said piston rings and said crossed-bar edges which appear insaid channels being wetted by mercury.

3. A coordinates selection switch comprising two groups of crossedconductive metal bars, one said group comprising parallel bars whichextend in a given direction and'which are disposed in planes at givenevenly distributed levels, the other group comprising parallel barswhich extend at right-angles to said given direction and which aredisposed at evenly distributed levels between said given levels, amoulded insulating plastics block receiving said crossed bars,cylindrical channels in checkerwork pattern extending through the blockand said crossed bars at said intersections thereof, pistons made ofmagnetic material, having metal rings and disposed in said channels, twoplates for hermetically closing said channels, secured to the two sidesof the said plastics block and formed on the outside surfaces thereofwith grooves, two groups of displaceable operating bars, the first groupbeing in the form of bars, sliding in a given direction in the groovesof said plate secured to one side of said block and the second group inthe form of bars sliding in a direction perpendicular to said givendirection in said grooves of said plate secured to the other side ofsaid block, magnets inserted into said operating bars at the samespacing from one another as said channels, the outside surface of thepiston rings and the crossed-bar edges which appear in said channelsbeing wetted by mercury.

1. A coordinates selection switch comprising two groups of crossedconductive metal bars, one said group comprising parallel bars whichextend in a given direction and which are disposed in planes at givenevenly distributed levels, the other group comprising parallel barswhich extend at right-angles to said given direction and which aredisposed at evenly distributed levels between said given levels, amoulded insulating plastics block receiving said crossed bars,cylindrical channels in checkerwork pattern extending through said blockand said crossed bars at the intersections thereof, pistons made ofmagnetic material, having metal rings and disposed in said channels,means for hermetically closing said channels, two groups of displaceableoperating bars, the first group being in the form of bars providingoperation in a given direction which are disposed on one side of saidblock and the second group in the form of bars providing operation in adirection perpendicular to said given direction which are disposed onthe other side of said block, magnets inserted into said operating barsat the same spacing from one another as the channels, the outsidesurface of said piston rings and said crossed-bar edges which appear insaid channels being wetted by mercury.
 2. A coordinates selection switchcomprising two groups of crossed conductive metal bars, one said groupcomprising parallel bars which extend in a given direction and which aredisposed in planes at given evenly distributed levels, the other groupcomprising parallel bars which extend at right-angles to said givendirection and which are disposed at evenly distributed levels betweensaid given levels, a moulded insulating plastics block receiving saidcrossed bars, cylindrical channels in checkerwork pattern extendingthrough said block and said crossed bars at the intersections thereof,pistons including a magnetic core, an insulating sheath and, disposedthereon, metal rings at discrete zones, said pistons being disposed insaid channels, means for hermetically closing said channels, two groupsof displaceable operating bars, the first group being in the form ofbars providing operation in a given direction which are disposed on oneside of said block and the second group in the form of bars providingoperation in a direction perpendicular to said given direction which aredisposed on the other side of said block, magnets inserted into saidoperating bars at the same spacing from one another as said channels,the outside surface of said piston rings and said crossed-bar edgeswhich appear in said channels being wetted by mercury.
 3. A coordinatesselection switch comprising two groups of crossed conductive metal bars,one said group comprising parallel bars which extend in a givendirecTion and which are disposed in planes at given evenly distributedlevels, the other group comprising parallel bars which extend atright-angles to said given direction and which are disposed at evenlydistributed levels between said given levels, a moulded insulatingplastics block receiving said crossed bars, cylindrical channels incheckerwork pattern extending through the block and said crossed bars atsaid intersections thereof, pistons made of magnetic material, havingmetal rings and disposed in said channels, two plates for hermeticallyclosing said channels, secured to the two sides of the said plasticsblock and formed on the outside surfaces thereof with grooves, twogroups of displaceable operating bars, the first group being in the formof bars, sliding in a given direction in the grooves of said platesecured to one side of said block and the second group in the form ofbars sliding in a direction perpendicular to said given direction insaid grooves of said plate secured to the other side of said block,magnets inserted into said operating bars at the same spacing from oneanother as said channels, the outside surface of the piston rings andthe crossed-bar edges which appear in said channels being wetted bymercury.